Coffee machine



FIG. 1 is a front perspective view of a coffee machine showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left-side view thereof;

FIG. 5 is a right-side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the figures depict portions of the coffee machine which form no part of the claimed design. 

CLAIM I claim the ornamental design for a coffee machine, as shown and described. 